A mass evacuation has been ordered at Union Station in Washington, DC by Metropolitan police. There are K-9 units investigating a suspicious package at the Amtrak section of the station.

Metro Transit Police have confirmed that "all entrances are reopening" and that "normal station operations are resuming" on their Twitter account. This follows nearly an hour of evacuation orders, with unconfirmed reports on the source of the emergency measures taken.

MTPD units at Union Station advise that normal station operations are resuming. All entrances reopening. AmtrakPD handing press. #wmata

Police had blocked off streets around Columbus Circle as people left the busy train station, which is one block away from the US Capitol.

"Our units have been told by law enforcement it was a good intent call and we are clearing the scene," DC Fire and EMS public information officer Vito Maggiolo told RT America before the all-clear was given.